In the current study, we evaluated various robust statistical methods for comparing two independent groups. Two scenarios for simulation were generated: one of equality and another of population mean differences. In each of the scenarios, 33 experimental conditions were used as a function of sample size, standard deviation and asymmetry. For each…

We consider here the problem of calculating the moments of binomial random variables. It is shown how formulae for both the raw and the central moments of such random variables may be obtained in a recursive manner utilizing Stirling numbers of the first kind. Suggestions are also provided as to how students might be encouraged to explore this…

If the diffusion model (Ratcliff & McKoon, 2008) is to account for the relative speeds of correct responses and errors, it is necessary that the components of processing identified by the model vary across the trials of a task. In standard applications, the rate at which information is accumulated by the diffusion process is assumed to be normally…

Numerous organizations collect and distribute non-aggregate personal data for a variety of different purposes, including demographic and public health research. In these situations, the data distributor is responsible with the protection of the anonymity and personal information of individuals. Microaggregation is one of the most commonly used…

Micceri (1989) examined the distributional characteristics of 440 large-sample achievement and psychometric measures. All the distributions were found to be nonnormal at alpha = 0.01. Micceri indicated three factors that might contribute to a non-Gaussian error distribution in the population. The first factor is subpopulations within a target…

The aim of this paper is to discuss different approaches to the quality (or uncertainty) of measurement data considering both historical examples and today's students' views. Today's teaching of data analysis is very much focussed on the application of statistical routines (often called the "Gaussian approach" to error analysis). Studies on…

This paper examines the use of a randomization-based activity to introduce the ANOVA F-test to students. The two main goals of this activity are to successfully teach students to comprehend ANOVA F-tests and to increase student comprehension of sampling distributions. Four sections of students in an advanced introductory statistics course…

The authors address the reliability of scores obtained on the summative performance assessments during the pilot year of our research. Contrary to classical test theory, we discussed the advantages of using generalizability theory for estimating reliability of scores for summative performance assessments. Generalizability theory was used as the…

Consensus among the majority of staff is essential for the development and consistent implementation of the Schoolwide Positive Behavior Interventions and Supports (SWPBIS) framework. At the universal level, a shared vision reflects consensus regarding operational definitions of behaviors (rules) and consequences. Yet, decades of research indicate…

It is more common for educational and psychological data to be nonnormal than to be approximately normal. This tendency may lead to bias and error in point estimates of the Pearson correlation coefficient. In a series of Monte Carlo simulations, the Pearson correlation was examined under conditions of normal and nonnormal data, and it was compared…

About one-quarter of Canadian adults and more than one-third of adults in the United States are obese. Obese children are at risk of becoming obese adults and can experience immediate health consequences such as psychosocial stress, elevated blood pressure and cholesterol, and abnormal glucose tolerance. Monitoring trends in childhood obesity is…

The Office of English Language Acquisition (OELA) has synthesized key data on English learners (ELs) into two-page PDF sheets, by topic, with graphics, plus key contacts. The topics for this report on English Learners (ELs) and NAEP include: (1) 2013 Reading Scores for Grades 4, 8, and 12: ELs vs. Non-ELs; (2) 2013 Mathematics Scores for Grades 4,…

The Office of English Language Acquisition (OELA) has synthesized key data on English learners (ELs) into two-page PDF sheets, by topic, with graphics, plus key contacts. The topics for this report on the retention and suspension of English Learners (ELs) include: (1) Percentage of ELs and Non-ELs Enrolled and Retained in Elementary School (Grades…

The Tuition Opportunity Program for Students (subsequently renamed the Taylor Opportunity Program for Students, or TOPS) was created by ACT 1375 of the 1997 Regular Legislative Session. The first college freshman class to receive TOPS awards entered postsecondary education in the fall of 1998. ACT 1202 of the 2001 Regular Legislative Session…

The aim of this paper is to provide an introduction of new imputation algorithms for estimating missing values from official statistics in larger data sets of data pre-processing, or outliers. The goal is to propose a new algorithm called IRMI (iterative robust model-based imputation). This algorithm is able to deal with all challenges like…